Method for attaching a spout to a flexible film pouch

ABSTRACT

A flexible film pouch includes an aperture to access its contents, and a closure means such as a re-sealable spout is applied over the aperture to permit sealed storage of the contents after opening. The closure means is attached to the flexible film pouch by means of a patch that is bonded to the inside of the pouch adjacent to the aperture. The patch is selected to have a mating surface that bonds with the inner surface of the pouch, where such bonding is preferably conducted by ultrasonic welding or adhesive bonding. The patch itself may have a hole that permits access to the contents of the pouch, or the closure means may include a cutting surface that tears a portion of the patch to permit access.

CROSS-REFERENCES TO RELATED APPLICATIONS

This is a Divisional Application which claims priority from U.S.application Ser. No. 11/471,930, filed Jun. 21, 2006, now U.S. Pat. No.8,075,189, issued Dec. 13, 2011, incorporated by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates generally to containers referred to as“flexible film pouches,” and more particularly refers to a method foraffixing a re-closeable spout to a flexible film pouch in order to allowthe spout to be used as a means of accessing the contents of the pouchand then resealed to secure the contents of the pouch.

BACKGROUND OF THE INVENTION

Flexible pouches are an attractive alternative to other forms ofconsumer packaging, including glass or plastic bottles, aluminum cans,and cartons. Pouches have distinctive practical and economic advantagesin that they lie flat when empty, thereby requiring less storage spaceand reducing handling and shipping costs as well as lower costs of bulkwaste. Flexible pouches are typically recyclable without processing andcan be produced at costs comparable to rigid containers. The appeal offlexible pouches to consumers over rigid containers includesconvenience: they are lightweight and easy to fit into small spaces;have a distinctive tactile appeal; and are more friendly to theenvironment and thus convey a lifestyle image more consistent with thatof many consumers. Flexible film pouches also tend to have greatersurface areas for displaying graphics and this creates more space formerchandising which further enhances the product, benefiting bothsuppliers and consumers alike.

Flexible pouches currently used in the packaging industry are comprisedof multi-layers of coextruded materials, conventionally between two andten layers, and more typically from four to six layers. The layers canbe made of polyethylene (PE), ethylene vinyl alcohol copolymer (EVOH),metal foil, or polyester (PET), along with a solvent or solvent basedadhesive to bind the adjoining layers.

Present art involves pouches that have been designed with a spout weldedto the top opening of the pouch body during the process of sealing thepouch closed. Most spouts are made of a high density PE and thismaterial does not readily adhere to other materials of non-similarcomposition. This makes affixing the spout to the pouch problematic.This is further complicated by difficulties with achieving a leak-proofseal of the spout to the pouch.

In addition to problems with the quality of seal, in some instances thecontents of the pouch is filled through the spout opening after it hasbeen attached to the pouch. This methodology is relatively slow,resulting in higher costs of manufacture and packaging. Consequently,spouted pouches can cost more than competing rigid containers requiringthem to be priced comparatively higher, and many consumers are unwillingto pay this added cost despite the distinctive design and appeal of thespouted pouch.

Another material which may be used for a spout is polypropylene (PP) butthe cost involved in affixing this spout to the body of the pouch isalso too high to gain strong consumer interest. As well, the present artfor spouts follows a common design, limiting brands owners fromachieving differentiation of their products, desired in the overallappearance of their packaging. Moreover, the application of spouts topouches for other uses aside from beverages, such as liquid foods aswell as household products, cosmetics, lotions, and the like are heldback by the limited range of spout sizes and lack of suitable andeconomical means of manufacture. Therefore while demand for pouches withspouts has been growing, spouted pouches have gained limited popularityas a packaging form. The present invention seeks to solve theseshortcomings with new opportunities for different spout configurationsby employing a different technology to seal the spout to the pouch andapply the spout to the outside of the pouch. These innovations willresult in a reliable and low cost method of applying an attractive andpractical re-closeable spout to flexible pouches and create newopportunities for spouted pouches to be utilized for a broad range ofproducts, including health and beauty, household, medical, automotiveand industrial products as well as low acid beverages, in a range ofpouch and spout sizes.

SUMMARY OF THE INVENTION

The shortcomings of the prior art are overcome in the present inventionthrough a combination of the method by which the spout is sealed to thepouch. The sealing method requires a flexible pouch to be manufacturedwith a patch (or strip) of thin film affixed to the inner surface of thepouch, to which a spout can be reliably attached. The spout, preferablycomposed of high density PE, is bonded to the patch or strip rather thanthe pouch body. For example, the pouch may include an external layer ofPE and a patch or strip would preferably include a surface of PE thatcould then be welded to the inner surface of the pouch. In a preferredembodiment, the welding is achieved though ultrasonic bonding, althoughother types of bonding may be used including bonding utilizing a processof applying heat and adhesives. A section of the pouch is cut away toexpose the patch or strip. When the spout flange is sealed to the patchor strip, it is positioned directly over the circular cut away portionof the pouch in order that it can be applied to the exposed patch orstrip material. In a first preferred embodiment, the patch or strip alsoincludes an aperture that can be used to fill the pouch as well asprovide ready access to the contents when the re-closable spout isopened. When the spout cap is twisted open and removed during itsinitial use, the contents of the pouch are allowed to flow through theaperture and the spout. In a second preferred embodiment, the patch orstrip provides a barrier that seals the pouch until ruptured by acutting mechanism located at the spout. When the spout cap is twisted toopen during its initial use, sharp protruding teeth on a cutting ringare engaged and lower to puncture the patch or strip material, then asthe cutting ring turns, the teeth cut through the patch or stripmaterial to create an aperture. The aperture allows the contents of thepouch to flow through the aperture and the pout.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention will become apparent fromthe following detailed description, taken in conjunction with theaccompanying drawings which illustrate, by way of example, the featuresof the invention, wherein:

FIG. 1 a is a front view, partially in shadow, of a first preferredembodiment of a thin film pouch and spout combination constructed of themethod of the present invention;

FIG. 1 b is a bottom view of the spout of FIG. 1 a;

FIG. 2 is an enlarged, cross-sectional view of the spout, patch, andpouch combination of FIG. 1 prior to attachment of the spout to thepatch;

FIG. 3 is an enlarged, cross-sectional view of the spout, patch, andpouch combination of FIG. 1 after attachment of the spout to the patch;

FIG. 4 a is a front view, partially in shadow, of a second preferredembodiment of a thin film pouch and spout combination constructed of themethod of the present invention;

FIG. 4 b is a bottom view of the spout of FIG. 4 a;

FIG. 5 is an enlarged, cross-sectional view of the spout, patch, andpouch combination of FIG. 4 prior to attachment of the spout to thepatch; and

FIG. 6 is an enlarged, cross-sectional view of the spout, patch, andpouch combination of FIG. 5 after attachment of the spout to the patch.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a first preferred embodiment of the present inventioncomprising a pouch 10 having a front wall 12 and a back wall 14preferably sealed at respective edges to form a fluid-tight reservoir.The pouch may include side panels (not shown) to expand the volume andmay further include a bottom portion that also increases the volume ofthe pouch, although the shape of the pouch and number of panels play norole in the specifics of the present invention.

The front wall 12 and rear wall 14 are preferably made of a multilayerlaminate of co-extruded material having between two and ten layers, andmore typically four to six layers. The layers can be made ofpolyethylene (PE), ethylene vinyl alcohol copolymer (EVOH), metal foil,polyester (PET), and solvent or solvent based adhesive to bind theadjoining layers. In order to create an opening in the pouch filmwhereupon a patch or strip of material will be applied, an aperture 16is formed in the front wall 12. The aperture 16 will typically be formedin the front wall during formation of the pouch, although the aperturemay be cut after the pouch is assembled.

Secured to the inside surface of the front wall 12 is a patch 18selected to bond with the inner surface of the front wall 12. Thepreferred method of bonding the two mating surfaces between the pouchand the patch 18 is with ultrasonic bonding techniques, although heatand adhesive techniques may also be used. As shown more clearly in FIGS.2 and 3, the mating surface 20 of the patch 18 that is intended to bondwith the inner surface 22 of the front wall 12 is constructed of a likematerial with the inner surface 22, or at least of a material selectedto promote bonding between the two surfaces. The preferred material isPE, although other materials are possible. Using ultrasonic bonding,adhesive bonding, heat welding, or other bonding techniques, the patch18 is affixed to the inner surface 22 of the pouch 10 such that thepatch 18 is behind the aperture 16 and may extend beyond the areadefined by the aperture and the patch 18 may be completely hidden by thefront wall 12. The patch 18 may include a smaller aperture 21, throughwhich the contents of the pouch 10 are intended to flow.

With the patch 18 in place bonded to the front wall 12 of the pouch 10,a closure means of the same material as the patch can then be affixedthereto. For example, a spout unit 24 can be directly affixed to thepatch 18 to provide a re-sealable closure means that also serves as apouring spout. The spout unit 24 may be comprised of a threaded cap 26that cooperates with a threaded spout 29 that has at its base, a flange28, although a snap-on cap or pull-spout such as those used on sportsdrink bottles may also be used. The flange 28 preferably includes asubstantially flat annular base 30 with an integrally formed, downwardlyprojecting ring portion 32 that forms the contact point for the flange28 to bond with the patch as shown in FIG. 3. With the flange 28 bondedto the patch 18 at the ring portion 32, the threaded cap 26 can beopened in order to evacuate the contents of the pouch and closed on thethreaded spout to seal the spout unit and therefore secure the contentswithin the pouch.

FIG. 4 illustrates a second or alternative embodiment of the presentinvention where the patch 38 may comprise a rectangular strip ofmaterial that extends from one edge 40 of the pouch to the opposite edge42, and may be attached at the welds of the front wall 12 and rear wall14. Unlike the previous embodiment, the patch 38 does not include a holebut rather is continuous across the aperture 16. When the closure meanssuch as spout unit 24 is bonded to the patch 38 as discussed above, theintegrity of the pouch is not breached and the pouch remains intact. Inthis embodiment, the spout unit 24 is equipped with cutting teeth 44(see FIG. 4 b) on the lower portion of the spout cap 26 that projectradially inwardly and/or downwardly below the surface of the annularbase 30. The spout 24 may be equipped with a spacer ring (not shown)that is discarded when the pouch is ready to open so that the cap can bepressed to bear against the patch 38 when the spacer ring is removed. Bytwisting the spout cap 26 against the patch 38, the cutting teeth 44tear the patch surface to open the pouch and allow access to itscontents. The tear in the patch 38 can be sealed by closing the spoutcap 26 against the flange 28 in the manner described above, thusallowing the pouch 10 to be resealed over and over.

FIGS. 5 and 6 illustrate the connection of the second preferredembodiment, where the teeth 44 on the cutting ring are shown rupturingthe patch 38 to create a patch flap 50 directed inwardly toward thepouch's interior. It is to be understood that the patch 18 of the firstembodiment or patch 38 of the second embodiment can be used with orwithout cutting teeth 44, and the cutting teeth 44 can be used witheither patch configuration. In addition to other types of closure meansdiscussed above, the mode of cutting or tearing the patch is notdeterminant of the second embodiment of the present invention and thedescription of cutting teeth are meant to be illustrative only.Perforations, pull-tabs, and other means of creating an opening in thepouch are considered within the scope of the invention.

1. A method for applying closure spout to a thin-film pouch to obtain are-sealable film pouch comprising the steps of: providing a thin-filmbeverage pouch having front and back walls defining a volumetherebetween, said front wall including an aperture and inner and outersurfaces; bonding a mating surface of a patch to the inner surface ofthe front wall behind said aperture, where the mating surface isselected to bond with the inner surface and the connection of the patchwith the front wall provides a fluid-tight seal; providing a closuremeans with a flange having a substantially flat annular base with anintegrally formed, downwardly projecting ring portion and a spout;affixing the substantially flat annular base of the closure means onsaid front wall of the thin-film beverage pouch; passing said downwardlyprojecting ring portion of the closure spout through said aperture suchthat a patch rupturing projection on said closure spout is brought inproximity with said patch; and bonding the ring portion to the patch. 2.The method of claim 1 where the bonding of the patch to the front wallis achieved by ultrasonic bonding.
 3. The method of claim 1 where thebonding of the spout to the patch is achieved by ultrasonic bonding. 4.The method of claim 1 where the closure means is a spout with acloseable lid.
 5. The method of claim 1 where the mating surface of thepatch and the inner surface of the front wall are of a common material.6. The method of claim 1 where the spout and the mating surface of thepatch are of a common material.
 7. The method of claim 1 furthercomprising providing said closure means with a cutting surface to tear aportion of said patch to access the pouch's volume.